BONE-MINERAL DENSITY AND BONE SIZE IN MEN WITH PRIMARY OSTEOPOROSIS AND VERTEBRAL FRACTURES

The bone mineral density (BMD) at the lumbar spine, proximal femur, an d total skeleton was evaluated in 38 men with primary osteoporosis and vertebral fractures. BMD of the patients was significantly reduced ov er all skeletal areas compared with controls. The Z-score of the lumba r spine (-2.8 +/- 0.9) was less than that of the other areas (P < 0.00 1) except the legs (-2.5 +/- 1.1) (p.n.s.) showing that bone loss had a tendency to be greater over the axial skeleton, Vertebral dimensions compared with age-matched controls were as follows: projected L2-L4 a rea (cm 2): 45.7 +/- 5.6 versus 53.7 +/- 3.6 (P < 0.001); vertebral wi dth (cm): 4.37 +/- 0.44 versus 4.90 +/- 0.36 (P < 0.001). Serum bioche mical parameters and testosterone levels were similar between osteopor otic and control men. We conclude that men with vertebral osteoporotic fractures have reduced vertebral BMD and vertebral dimensions compare d with age-matched controls. Thus, these findings indicate that the ac hievement of a reduced bone size at the end of the growth period or a failure of periosteal increase during adult life is likely to contribu te to the pathogenesis of the vertebral fractures observed in older me n.